Improvement in rock-drills



2 Sheets--S'heet 1.

G. HQREYNOLDS.

Ruck-Drill.

Patented April 20,1875.

i:IMI mit n THE GRAPHIC C0 PH T ZSheets--Sheet'Z- G. H. REYNOLDS.

Rock-Drill. No. 162,419. Patented Apri|20,1875.

THE GRAPHIC C0.PHOT0.LITI1.39&41 PARK PLAGEJLY.

UNITED STATES PATENT JOEEroE.

GEORGE H. REYNOLDS, OF NEW YORK, N. Y., ASSIGNORTO HIMSELF AND CORNELIUSH. DELAMATER, OF SAME PLACE.

IMPROVEMENT IN ROCK-DRHLS.

Specification forming part of Letters Patent No. 162,11l9, dated April2i), 1875; application filed January 29, 1875.

To all whom 'it may concern:

Be it known that I, GEORGE H. REYNOLDS, of the city, county, and Stateof New York, have invented certain new and useful Improvements inRock-Drills; andl do hereby declare that the following is a full, clear,and exact description of the saine, reference being had to theaccompanying drawing forming part of this specification.

This invention more particularly relates to machines for drilling rock,although the valve which I employ in the machine, and which is of thekind that uses the propelling fluid from the main cylinder to throw it,is also applicable to direct-acting engines for other purposes.

The main object of the invention is to construct a rock-drill whichshall be so simple that it can be produced at a reduced cost, and at thesame time be more durable than other rock-drills now in use.

The invention consists in certain novel and advantageous constructionsand combinations of parts relating to the ports or passages and valveused to operate the piston of the drillcylinder, and the devices used tofeed the latter, together with the drill-piston Working therein. Itlikewise consists in a novel construction of the drill-piston, inconnection with the inlet-ports in its cylinder, and an extension of thelatter beyond the pistons stroke, whereby, while the piston is preventedfrom striking the cylinder-heads, provision is made for starting it whenstopping at the end of its full stroke.

Either steam or compressed air may be used as the propelling fluid, butit will suffice in the subsequent description to refer only to steam,and to describe the piston-valve as a steam-thrown one.

Figure l represents a longitudinal sectional elevation of a rock-drillas carried by a tripod, and constructed in accordance with my invention.Fig. 2 is a partly sectional rear view of the same.

A is the main or drill cylinder, constructed to be capable of adjustmentalong and within a cradle, B, and having a cylindricalsteam or valvechest, C, mounted on it in transverse relation with the drill-cylinder,the object of which arrangement will be hereinafter explained. D D arethe heads of the drill-cylinder, and E its piston. This cylinder A andvalve-chest C are provided with ports or passages b b', d d', and f f1.The ports b b are inlets to the main cylinder, and separately connect,at suitable distances apart, the central portion of the valve-cylinderwith the opposite ends of the main cylinder 5 but the latter is extendeda sufficient distance beyond these ports to provide for the piston Ecushioning itself by steam contained within the cylinder, and so preventthe piston from striking the cylinder-heads. The ports d d are outletsfrom the intermediate or body portion of the main cylinder A to the endsof the valve-cylinder C, and the ports ffl are exhaustports from theends of the valve-cylinder, communicating with a general outlet, j. Thesteam is admitted to the central portion of the valve-chest by a portand pipe, g. Attached to the one end of the piston E is the drill-bar G,While through and within the opposite end of the cylinder A a shaft, H,is litted to turn. This shaft is of angular or other equivalentconstruction Where it projects Within the cylinder, and enters acorrespondiugly-shaped socket, H', in and throughout the greater portionof the length of the piston E, so that said shaft, when turning in thecylinder-head, also rotates the piston with its attached drill, without,however, restrict-ing the reciprocating movement of the piston. Thisshaft H is also constructed, outside of the cylinder A, to form a screw,which works through a nut or screw-box, o, in the end of the cradle B,for the purpose of feeding the drill. In this Way I make the same shaftor screw H feed the drill forward and rotate it, the drill being fedforward or downward as, fast as the drill-bit enters the rock, and atthe same time being rotated so as to cut over the Whole surface of thebottom of the hole drilled, thus keeping the hole round, and preventingthe bit from sticking.

I is the valve, arranged to freely reciprocate Within its cylinder C,and having air dashpots at either end to cushion it, as hereinafterdescribed. This valve, which is provided ports b b.

The operation of the valve as controlling the piston is as follows:Steam is admitted to the valve-chest between the heads or pistons of thevalve I. Supposing said valve to be in position to pass steam by theport b to the back of the piston E, the latter is urged forward untilthe port cl is uncovered, when steam passes from the cylinder by theport d to the one outer surface of the piston-valve I,

and so reverses the latter or opens the portb to the steam, while itopens the port b and port d to the exhaust f. The piston E beingreversed, a like action takes place in due course as regards the steampassing from the cylinder by the port d', to again throw or change thepositions of the valve,Y and to exhaust from the ports b and d throughthe outlet f. In this way a continuous reciprocating action is kept up,for, so long as'there is sufficient pressure to move the piston E, thesame pressure is more than sufficient to actulate the valve I.

As hereinbefore described, the extension of the cylinder A beyond theports b b provides for the cushioning of the piston E, or prevents thelatter from knocking` out the heads D I) ofthe cylinder. Whenever,however, the piston shall have overshot the ports b b', and stops at theendof its full stroke, then a difficulty would arise in starting itagain. To vobviate this I form grooves on m in the piston E, near itsends, and provide per'forations n a from said grooves to or through theouter ends of the piston, so that, on said grooves coming into line withthe ports b b', steam will be passed, as required, to start the pistonagain.

By the arrangement of the valve I with its cylinder G in transverserelation with the cylinder A, the drill-cylinder may be rocked orinclined, to work the drill at different angles, without endangering theshifting of the valve by gravity, or causing it to move out of ahorizontal position.

The air dash-pots applied to effect the cushioning ofthe valve I areshown at J J in Fig. 2, the same being constructed on the exterior ofthe heads of the valve-cylinder C, and open to the atmosphere on theexterior of the cushioning-pistons, which operate inwardly to effectcompression or cushioning, whereby not only may the valve be operatedmore readily by hand when required, but a stufng-box in eithercylinder-head is dispensed with. These dash-pots are perforated with oneor more air holes or ports, s s', extending laterally through them, theobject of which will here be explained.

When the pistons on the ends of the valverod are alternately thrown totheir full extent in an outward direction, the dash-pots are filled withair on the inner faces of said pistons through the ports s s', and uponthe pistons working inward they pass freely till the ports s arecovered; then, there being no more escape for the air through the ports,the pistons are cushioned by the air within the inner ends of thedash-pots, to prevent injury Vor breakage in the rapid working of thedrill.

It is preferred to mount the rock-drill upon a tripod, K, except whenusing the drill for tunneling, when it may be mounted upon a column, andto do which it is removed from the tripod by simply drawing a bolt, M,and lifting out the cradle B, bringing with it the drill-cylinder andits accompanying parts.

The attachment of the machine to the tripod is exceedingly simple. Thus,the one bolt M serves to attach the tripod by its straps K to the cradleB, with every facility for the adjustment of the latter by rocking it,and the cradle is prevented from spreading by a thimble or fast socket,L, bearing at its ends against the straps K', and which is free to turnupon the bolt, or the latter within it. This mode of attaching themachine to the tripod does not, however, constitute part ot' the presentinvention.

I claim- 1. The air dash-pots J J, constructed on the exterior of theheads of the valve-cylinder (l, and with their cushioning pistonsoperating inwardly to effect compression, whereby a stuffing-box for thevalve-stem in either cylinder-head is dispensed with, and said stem mayreadily be operated by hand when required, substantially as specified.

2. The combination of the ports or passages b b', l d', and ffl, therocking drill-cylinder A, the drill-piston E, the piston-valve I, andthe cylinder C, essentially as shown and described. I

3. The combination of the screw feeding and rotating shaft H, connectedwith and feeding the cylinder A, and leaving the piston E free to turnwith, but sliding on, said shaft, and the nut or screw box c,substantially as specified.

et. The combination, with the cylinder A, having its ends extendedbeyond the ports b b', of the grooves m and perforations u in the endsof the piston E, essentially as and for the purposes herein set forth.

GEO. H. REYNOLDS.

Witnesses: i

BENJAMIN W. HOFFMAN, FRED. HAYNns.

